1. Field of the Invention
The present invention relates to a structure for holding a voltage detecting terminal.
2. Description of the Related Art
A power supply device that connects a plurality of batteries in series is mounted on motors, such as a hybrid car and an electric car. In this type of power supply device, a busbar module is mounted on a plurality of batteries (hereinafter referred to as a battery assembly) in which electrode columns of a positive electrode and a negative electrode are alternately arrayed and superimposed, and the respective batteries are connected in series. The busbar module includes a plurality of busbars each of which electrically connects a positive electrode and a negative electrode of the batteries adjacent to each other, a plurality of voltage detecting terminals each of which is connected to each busbar and detects the voltage of each battery, a plurality of electric wires (voltage detecting wires) connected to the voltage detecting terminals, respectively, and a plate made of insulating resin that holds the busbars and the voltage detecting terminals (refer to PTL 1).
The busbar includes a plate material made of conductive metal, and is provided with a pair of insertion holes that allow an electrode column as the positive electrode and an electrode column as the negative electrode in the batteries adjacent to each other to pass therethrough, respectively. The voltage detecting terminal has an electric contact portion that detects the voltage of a battery in contact with the busbar, and a crimping portion that is connected to the electric contact portion and has an electric wire crimped thereat. The electric contact portion includes a plate material made of conductive metal, and is provided with an insertion hole that allows one of the two electrode columns, to which the busbar is connected, to pass therethrough.
The plate is integrally formed with a plurality of first housing portions that are formed in conformity with the size of the battery assembly as a whole and houses the busbars and the electric contact portions of the voltage detecting terminals, a coupling portion that couples the first housing portions adjacent to each other, and a second housing portion that is connected to a first housing portion and houses the crimping portion of each voltage detecting terminal.
The power supply device configured in this way is assembled as follows. First, the busbar is housed in the first housing portion of the plate, and the busbar is held by the first housing portion. Subsequently, as for the voltage detecting terminal, the electric contact portion is superimposed on and held by the busbar of the first housing portion, and the crimping portion is housed in the second housing portion.
If the plate to which the busbar and the voltage detecting terminal are attached in this way is mounted on the battery assembly, the electrode columns of the positive electrode and the negative electrode are respectively inserted into the pair of insertion holes of the busbar, and one electrode column passed through the insertion hole is inserted into the insertion hole of the electric contact portion of the voltage detecting terminal. Accordingly, one end surface of the busbar is arranged in contact with the two electrode columns, respectively, and the other end surface of the busbar is arranged in contact with the electric contact portion of the voltage detecting terminal. Then, as a nut is screwed along a groove formed in each electrode column, the busbar and the voltage detecting terminal are electrically connected to the pair of electrode columns, respectively.
Meanwhile, as illustrated in FIG. 5, a plate-shaped holding portion 107, which is connected to an electric contact portion 105 and extends in a planar direction, is provided at a related-art voltage detecting terminal 101, in addition to a crimping portion 103. As illustrated in FIG. 6, as the holding portion 107 abuts against a supporting surface 113 formed in a plate 109 and the crimping portion 103 is housed in a second housing portion 115, the voltage detecting terminal 101 is held by the plate 109 in order to be held by a first housing portion 111 of the plate 109.
[PTL 1] JP-A-2011-18499